> On Jan 24, 2026, at 09:16, David G. Johnston <[email protected]>
> wrote:
>
>
> On Fri, Jan 23, 2026 at 5:57 PM David G. Johnston
> <[email protected]> wrote:
>
> "A nonrecursive DROP COLUMN (i.e., ALTER TABLE ONLY ... DROP COLUMN)
> never removes any descendant columns, but instead marks them as
> independently defined rather than inherited."
>
> This part is now undocumented, it was only mentioned in this paragraph.
>
> True, it's left implied instead of explicitly stated. Any column that exists
> on a child but not the parent is by definition "independently defined". So
> if either ONLY is supplied or the rules for cascading delete are not met the
> result is children with independently defined columns with that name.
>
> The original note was wrong anyway for the two-parent case - the second
> parent prevents the marking as independent when the first parent's column is
> dropped.
>
> Decided to test this one and I see the original wording was correct and we
> will need to keep a note that in the two-parent ONLY case the un-dropped
> children are marked both dependent and independent.
>
> Change:
>
> <para>
> For inheritance setups, a descendant column is removed only if both of
> the
> following are true: this is the only parent defining the column, and
> the column
> was never independently defined in the descendant.
> </para>
>
> To:
>
> "For inheritance setups, a descendant column is removed only if all the
> following are true: ONLY is not specified, no other parent defines the
> column, and the column is not marked as having been independent. Otherwise,
> the descendant column is instead marked as having been independent.
>
> If we think that deserves a bit longer explanation about that/why/how a
> column can be both dependent and "having been independent" we should
> cross-reference to a more appropriate location. Here we just state this is
> one way that condition can materialize.
>
> David J.
>
Thanks a lot for the test. Included in v7.
Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/
